Editor 's note : José Miguel Vivanco is executive director of the Americas Division of Human Rights Watch , a nonprofit organization that seeks to protect people 's rights . A lawyer from Chile , he was educated there , in Spain and at Harvard Law School .

José Miguel Vivanco says conviction of Peru 's ex-president is a warning to those who deny human rights .

-LRB- CNN -RRB- -- Peruvians are celebrating an extraordinary victory this week : the conviction of their former president , Alberto Fujimori , for death squad killings carried out during his rule in the 1990s .

The Peruvian Supreme Court found him guilty of egregious human rights abuses , including the massacre of innocent civilians , and sentenced him to 25 years in prison -- a stiff message to other leaders that justice can eventually catch up to even the most powerful .

It is one of the first times a nation 's own independent courts have convicted a former leader for such serious human rights crimes and it sets an important precedent for a region that suffered so much from political violence and rights violations . Equally significant , the ruling came after a lengthy televised trial , which was clearly fair to the defendant -- despite Peru 's previous history of authoritarianism and weak rule of law .

Fujimori came to office in 1990 on the promise of crushing a vicious Maoist insurgency but , in the process of restoring order , he corrupted and weakened Peru 's most vital government institutions -- including parliament , the courts and law enforcement . Just a few years ago , Fujimori had near-total control of Peru 's judiciary .

For a decade , his government used bribery , extortion , and intimidation to concentrate power in the presidency , subverting the democratic process and eliminating normal checks by the judiciary , legislature , and media on government abuses .

He led Peru from 1990 to 2000 , presiding over the war with the Shining Path guerrillas and the Tupac Amaru Revolutionary Movement . He was convicted of authorizing killings and kidnappings by paramilitary death squads . Fujimori is to be tried separately on multiple corruption charges .

The landmark decision fits within a global trend of increasing accountability for former heads of state . Just 20 years ago , it was exceedingly rare for even the most brutal leaders to be brought to book . In the late 20th century , Mao Zedong , Idi Amin , Milton Obote , Ferdinand Marcos , Anastasio Somoza , Jean-Claude `` Baby Doc '' Duvalier and Mobutu Sese Seko , to name just a few , were never brought to trial .

Since then , however , the tide has turned . In October 1998 , London police arrested General Augusto Pinochet on a warrant from a Spanish judge for human rights crimes . The arrest and the subsequent decisions by the British House of Lords to reject Pinochet 's claim of immunity were a wake-up call to tyrants everywhere , but more important , they gave hope to victims elsewhere that they too could bring their tormentors to justice .

In country after country , particularly in Latin America , victims were inspired to challenge the amnesty laws of the 1980s and 1990s that had allowed the perpetrators of atrocities to go unpunished and , often , to remain in power . Thanks to these efforts , former leaders in Argentina , and Uruguay have also faced human rights trials .

Pinochet 's arrest also strengthened a nascent international movement -- spurred by the killings in Bosnia and Rwanda , and facilitated by the end of the Cold War -- to make certain the worst abuses are punished .

After the creation of UN tribunals for the former Yugoslavia and Rwanda , the world established the International Criminal Court -LRB- ICC -RRB- to prosecute genocide , crimes against humanity and serious war crimes when national courts are unable or unwilling to do so .

The ICC is now investigating crimes in the Central African Republic , Uganda and the Democratic Republic of the Congo , and in March the court indicted President Omar al-Bashir of Sudan on charges of crimes against humanity in Darfur .

The Fujimori case stands out , though , because it was Peru 's national court system which demonstrated the will , capacity , and independence to try its former president .

A second panel of the Supreme Court will now review an appeal by Fujimori . One can hope the second panel will be as transparent and fair as the first .

Even after this verdict , impunity for past atrocities continues to be a major problem in Peru and throughout the region . It is likely , however , that yesterday 's verdict will help give momentum to efforts currently underway in many Latin American countries to bring other human rights violators to justice .

The verdict will also send a powerful message to current heads of state who may be tempted to use abusive tactics to resolve their political problems . As Fujimori discovered yesterday , crimes they may be able to get away with while in power can come back to haunt them years later .

The opinions expressed in this commentary are solely those of José Miguel Vivanco .

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José Miguel Vivanco : Peruvian court verdict in Fujimori case sends strong message

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Fujimori was convicted for allowing death squads to murder innocents

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Since Pinochet case , Vivanco says , courts have been holding leaders accountable

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Vivanco : Leaders who deny human rights may suffer for it years later